In__________, eachstation is forced to send only at the beginning of the time slot.
A)
pure ALOHA
B)
slotted ALOHA
C)
both (a) and (b)
D)
neither (a) nor (b)

1 Answer

Answer :

slotted ALOHA

Related questions

Description : A certain population of ALOHA users manages to generate 70 request/sec. If the time is slotted in units of 50 msec, then channel load would be a. 4.25 b. 3.5 c. 350 d. 450

Last Answer : b. 3.5

Description : With Slotted Aloha, a …………. sends out small clock tick packets to the outlying stations. A. distributed clock B. synchronized clock C. centralized clock D. Digital clock

Last Answer : C. centralized clock

Description : Suppose there are n stations in a slotted LAN. Each station attempts to transmit with a probability P in each time slot. The probability that only one station transmits in a given slot is _______. a. nP(1 – P)n – 1 b. nP c. P(1 – P)n – 1 d. n P (1 – P)n – 1

Last Answer : a. nP(1 – P)n – 1

Description : In pure ALOHA, the vulnerable time is ______the frame transmissiontime. A) the sameas B) two times C) three times D) none of the above

Last Answer : two times

Description : The maximum throughput for pure ALOHA is________per cent. A) 12.2 B) 18.4 C) 36.8 D) none of the above

Last Answer : 18.4

Description : A pure ALOHA Network transmits 200 bit frames using a shared channel with 200 Kbps bandwidth. If the system (all stations put together) produces 500 frames per second, then the throughput of the system is ______. a. 0.384 b. 0.184 c. 0.286 d. 0.58

Last Answer : b. 0.184

Description : For pure ALOHA, the maximum channel utilization is a. 100% b. 50% c. 36% d. 18%

Last Answer : d. 18%

Description : Suppose there are n stations in a slotted LAN. Each station attempts to transmit with a probability P in each time slot. The probability that only one station transmits in a given slot is .................. (1) nP(1-P)n-1 (2) nP (3) P(1-P)n-1 (4) nP(1-P)n-1

Last Answer :  nP(1-P)n-1

Description : _______uses four twisted-pair cables that connect eachstation toa commonhub. A) 10Base5 B) 10Base2 C) 10Base-T D) 10Base-F

Last Answer : 10Base-T

Description : In_____, each station is allocateda time slotduring which it can send data. Each stationtransmits its data in itsassigned time slot. A) FDMA B) TDMA C) CDMA D) none of the above

Last Answer : TDMA

Description : Inslotted ALOHA, the vulnerable time is ______ the frame transmissiontime. A) the sameas B) two times C) three times D) none of the above

Last Answer : the sameas

Description : In IEEE 802.11, the access method used in the DCF sublayer is _________. A) ALOHA B) CSMA/CA C) CSMA/CD D) none of the above

Last Answer : CSMA/CA

Description : The Aloha protocol is an OSI _______ protocol for LAN networks with broadcast topology A. layer 1 B. layer 4 C. layer 2 D. layer 3

Last Answer : C. layer 2

Description : In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the (A) Range is 15°F (B) Approach is 10°F (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : Nusselt number (for forced convection heat transfer) is a function of the __________ number. (A) Prandtl (B) Reynolds (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : Forced circulation evaporators are normally used for concentrating liquids having (A) Scaling characteristics (B) High viscosity (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : In a forced draft cooling tower, water is cooled from 95 to 80°F by exposure to air with a wet bulb temperature of 70°F. In this case, the (A) Range is 15°F (B) Approach is 10°F (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : Consider the following statements: 1. when an electric bulb is switched on, the resistance of its tungsten filament increases. 2. the resistance of pure metals increases on heating. Which of the above statements is/are correct? (a) Both 1 and 2 (b) only 1 (c) only 2 (d) Neither 1 nor 2

Last Answer : Ans:(a)

Description : In a pure market economy, which of the following is a function of the price? I. provide information to sellers and buyers , II. provide incentives to sellers and buyers a. I only b. II only c. both I and II d. neither I nor II

Last Answer : c. both I and II

Description : A pure ALOHA Network transmit 200 bit frames using a shared channel with 200 Kbps bandwidth. If the system (all stations put together) produces 500 frames per second, then the throughput of the system is .............. (A) 0.384 (B) 0.184 (C) 0.286 (D) 0.586

Last Answer : (B) 0.184

Description : A data terminal serves as an a. Effector b. sensor c. both a and b d. neither a nor b

Last Answer : both a and b

Description : Gigabit Ethernet access methods include _______ mode. A) half-duplex B) full-duplex C) both (a) and (b) D) neither (a) nor (b)

Last Answer : both (a) and (b)

Description : In___________ thereis alwaysa transition at the middle of the bit, but thebit values are determined at the beginningof the bit. If the nextbit is 0, there is a transition; if the next bit is 1, there is none. A) Manchester B) differential Manchester C) both (a) and (b) D) neither (a) nor (b)

Last Answer : differential Manchester

Description : In_______encoding, the duration of the bit is divided into twohalves. Thevoltage remains at one level during thefirst half and moves to the other level in the second half. The transition at the middle of the bit ... Manchester B) differential Manchester C) both (a) and (b) D) neither (a) nor (b)

Last Answer : both (a) and (b)

Description : The idea of RZ andthe ideaof NRZ-I are combined into the ________ scheme. A) Manchester B) differential Manchester C) both (a) and (b) D) neither (a) nor (b)

Last Answer : differential Manchester

Description : The idea of RZ andthe ideaof NRZ-L are combined into the ________ scheme. A) Manchester B) differential Manchester C) both (a) and (b) D) neither (a) nor (b)

Last Answer : Manchester

Description : In______, the changeor lackof change in the level of the voltagedetermines the value of the bit. A) NRZ-I B) NRZ-L C) both (a)and (b) D) neither (a) nor (b)

Last Answer : NRZ-I

Description : In_____, the level of the voltagedetermines the valueof the bit. A) NRZ-I B) NRZ-L C) both (a) and (b) D) neither (a) nor (b)

Last Answer : NRZ-L

Description : _________ does not provide reliable end to end communication. a. TCP b. UDP c. Both TCP and UDP d. Neither TCP nor UDP

Last Answer : b. UDP

Description : A ……………………….. is built from the information exchanged by routing protocols. A. static routing table B. dynamic routing table C. both a and b D. neither a nor b

Last Answer : B. dynamic routing table

Description : . A ………………………... is constructed manually by the system administrator using the route command. A. static routing table B. dynamic routing table C. both a and b D. neither a nor b

Last Answer : A. static routing table

Description : What is the difference between the market segments at the beginning of the round to the final round? a. They all drift at an average rate of .7; down and to the right. b. The fine cuts ... not. e. The High, Traditional and Low segment rough cuts overlap but all the remaining segments do not.

Last Answer : b. The fine cuts overlap in the beginning and in year 8; only the rough cuts overlap.

Description : Pick out the correct statement. (A) A forced vortex occurs when fluid rotates as a solid about an axis (B) In laminar flow, Newton's law of viscosity does not apply (C) A free vortex occurs, when fluid rotates as a solid (D) In turbulent flow, there are neither cross-currents nor eddies

Last Answer : (A) A forced vortex occurs when fluid rotates as a solid about an axis

Description : If an ideal solution is formed by mixing two pure liquids in any proportion, then the __________ of mixing is zero (A) Enthalpy (B) Volume (C) Both 'a' & 'b' (D) Neither 'a' nor 'b'

Last Answer : (C) Both 'a' & 'b'

Description : If two pure liquid constituents are mixed in any proportion to give an ideal solution, there is no change in (A) Volume (B) Enthalpy (C) Both (A) & (B) (D) Neither (A) nor (B)

Last Answer : (C) Both (A) & (B)

Description : In IEEE 802.11, _______ isan optionalaccess method that can be implemented inan infrastructure network (not in an ad hocnetwork). A) DCF B) PCF C) either (a) or (b) D) neither (a) nor (b)

Last Answer : PCF

Description : In IEEE 802.11, a BSS with an AP is sometimes referred toas ____________. A) an ad hocarchitecture B) an infrastructurenetwork C) either (a) or (b) D) neither (a) nor (b)

Last Answer : an infrastructurenetwork

Description : In IEEE 802.11, a BSS without an AP is called an _________. A) an ad hocarchitecture B) an infrastructurenetwork C) either (a) or (b) D) neither (a) nor (b)

Last Answer : an ad hocarchitecture

Description : ________ is actually a multiport repeater. It is normally usedto createconnections between stations in a physical star topology. A) An activehub B) A passivehub C) either (a)or (b) D) neither (a) nor (b)

Last Answer : An activehub

Description : _______ ispart of the media; its location in the Internet model is below thephysical layer. A) An activehub B) A passivehub C) either (a)or (b) D) neither (a) nor (b)

Last Answer : A passivehub

Description : In astar-topology Ethernet LAN, _______ is just a point where the signals coming from different stations collide; it is thecollision point. A) An activehub B) A passivehub C) either (a)or (b) D) neither (a) nor (b)

Last Answer : A passivehub

Description : _________is just aconnector. A) An activehub B) A passive hub C) either (a)or (b) D) neither (a)nor (b)

Last Answer : A passive hub

Description : A backbone is usually a ______. A) bus B) star C) either (a)or (b) D) neither (a) nor (b)

Last Answer : either (a)or (b)

Description : Analog-to-analog conversionis needed if the available bandwidthis _______. A) low-pass B) band-pass C) either (a)or (b) D) neither (a) nor (b)

Last Answer : band-pass

Description : A(n)_________ signal is a composite analogsignal with an infinite bandwidth. A) digital B) analog C) either (a)or (b) D) neither (a) nor (b

Last Answer : digital

Description : Signals can be ________. A) analog B) digital C) either (a)or (b) D) neither (a) nor (b)

Last Answer : either (a)or (b)

Description : A ring SONET network can be _________. A) unidirectional B) bidirectional. C) either (a) or (b) D) neither (a) nor (b)

Last Answer : bidirectional.

Description : A linear SONET network can be __________. A) point-to-point B) multipoint C) either (a) or (b) D) neither (a) nor (b)

Last Answer : point-to-point

Description : SDH hasdefined ahierarchy of signals called ________. A) STSs B) STMs C) either (a) or (b) D) neither (a) nor (b)

Last Answer : STSs

Description : ______ isa standard developed by ITU-T. A) SONET B) SDH C) either (a) or (b) D) neither (a) nor (b)

Last Answer : either (a) or (b)